The present invention relates generally to electric motors, such as three-phase synchronous, three-phase asynchronous, single-phase alternating-current (AC) electric motors and direct-current (DC) electric motors.
In a conventional electric motor, it is necessary to change the voltage or frequency of the power supply in order to adjust the speed of the motor. Additionally, the rotating speed of a conventional AC electric motor cannot be faster than the synchronous speed corresponding to the power frequency. Accordingly, the rotating speed range of a conventional AC electric motor is not large enough, and it is also difficult to govern its speed. The configuration of a conventional DC electric motor is complex, and its performance need to be improved.
It is an object of the present invention to provide an intelligent AC electric motor and an intelligent DC electric motor. The rotating speed of the intelligent AC electric motor can be greater than the synchronous speed corresponding to the power frequency, so that the speed range is enlarged and the speed control is improved. The intelligent DC electric motor is provided with a simpler configuration and better performance.
The object of the present invention is achieved by the addition of a control gate circuit structure to a conventional electric motor.
The intelligent motor may be divided into an intelligent AC electric motor and an intelligent DC electric motor. Its operating performances, such as rotating speed and the like, are changed by various control means including a computer. The intelligent electric motor consist of a relevant motor and a non-contacting control gate circuit, and all the means are assembled into the housing of the intelligent electric motor.
Preferably, the control gate circuit in an intelligent AC electric motor, including an intelligent synchronous electric motor, an intelligent asynchronous electric motor, an intelligent single-phase electric motor and the like, causes the stator windings of the electric motor to be switched to the phase sequences of the power-supply in turn and periodically according to a predetermined operation mode. The objects of changing the motors performance and governing its rotating speed can be accomplished via an additional rotating magnetic field, xc2x1xcex4 that is generated by such switching.
Preferably, the control gate circuit in an intelligent DC electric motor causes the stator windings of the electric motor to be switched to the power-supply polarities in turn and periodically according to a predetermined operation mode. One additional rotating magnetic field, which is generated by switching the stator windings of the electric motor to the power-supply polarities in turn and periodically, can achieve the objects of changing the electric motor""s performance and governing the rotating speed of the electric motor.
Preferably, the intelligent AC electric motor employs a cage rotor such that asynchronous operation of the intelligent AC electric motor can be implemented.
Preferably, the intelligent AC electric motor employs the permanent magnet rotor or the direct-current exciting rotor of a synchronous motor, so that synchronous operation of the intelligent DC motor can be implemented.